I’m at Google today and even with all the resources, I am absolutely most bottlenecked by the Presubmit TAP and human review latency. Making CLs in the editor takes me a few hours. Getting them in the system takes days and sometimes weeks.
There are a lot of technical challenges in maintaining code health in a monorepo with 100k+ active contributors, so teams and individuals get a lot of plausible excuses for kicking the problem down the road, and truly improving code health is not appropriately incentivized. One common occurrence is a broken monorepo, so one just waits until someone fixes the monorepo, and you retry submitting your code again. It's such a common occurrence that people generally do not investigate brokenness, and maybe the monorepo wasn't broken but your code change actually made things even flakier, but no one would be able to distinguish that from a broken monorepo that eventually got fixed when no one bothers to check anymore.
Maybe at Google they can afford that, where I worked at some point I was working 2 or 3 projects switching between issues. Of course all projects were the same tech and mostly the same setup, but business logic and tasks were different.
If I have to wait 2-3 hours I have code to review, bug fixes in different places to implement. Even on a single project if you wait 2 hours till your code lands test env and have nothing else to do someone is mismanaging the process.
It's an overpaid overglorified boring job (obv. outside all the 'cool' research-y projects).
You just need an AI agent to shepherd it through the slow process for you while you work on something else!